The present invention relates to a portable, self-contained, X-ray apparatus that digitally processes, displays, stores, and/or transmits electronic radioscopic images of sealed packages, containers and other objects on location for security, customs, and other non-destructive purposes. For example, one application for the present invention is to determine if a closed suitcase or sealed package contains a bomb or contraband.
There are many instances in the security or customs field when it is necessary to examine or inspect, in a non-destructive way, the contents of a closed package, box, suitcase, or other container. For example, customs departments are routinely charged with the responsibility of inspecting the contents of incoming packages to make sure such packages do not contain explosives, drugs or other contraband. Similarly, terrorists, criminals, or other enemies frequently carry out their criminal acts of terrorism or war by planting bombs in sealed containers or packages, and then sending the sealed containers/packages to the intended victims, e.g., through the mail, or planting the sealed container/packages at the desired target, e.g., by leaving a locked suitcase or a sealed box containing a bomb in a busy public transportation terminal. When security personnel encounter suspicious packages or other containers being sent through the mail, or left at public transportation terminals, or other locations, they must perform a careful inspection of such containers to ascertain their contents.
When suspicious containers, such as suitcases, sealed boxes/packages are discovered, they generally must be examined or inspected on location in a non-destructive manner. If the non-destructive examination reveals the presence of explosives (e.g., a bomb) or contraband (e.g., drugs), then the container and its contents must be safely disposed of. If, on the other hand, the examination reveals the absence of explosives or contraband, then the container may be handled in a normal manner, i.e., forwarded on to its owner or addressee.
Unfortunately, the process used to examine or inspect a suspicious sealed box, package, suitcase or other container must not trigger any bomb that may be concealed inside. Thus, for example, as a safety precaution, the suspicious container may not be opened because such opening may trigger any bomb contained therein. Similarly, the suspicious container may not be moved because such movement could likewise trigger a hidden bomb. Further, the suspicious container may not be examined with high doses of radiation because such radiation, if significantly greater than normal background radiation, could also trigger a hidden bomb. What is needed, therefore, is a non-invasive technique for inspecting the contents of a suspicious container without requiring that the container be opened, moved, or subjected to high levels of radiation.
Heretofore, suspicious containers of the type referenced above have been examined using portable, generally low power, X-ray generators and highly sensitive X-ray film as a detector, with many attendant problems. For example, the film used with such conventional film-based radiography systems, has a poor shelf life in the environment typical to field inspections, which means that its sensitivity may vary considerably. The operator must then go back to the object under test for each image taken until the correct exposure and orientation is obtained. Once such image is taken, it must then be processed with a portable chemical laboratory with the attendant delays of such efforts.
It is also known in the art to improve the conventional film-based radiography systems by adapting certain types of industrial imaging systems as an image detection system to overcome some of the field problems. Such systems typically use intensified, low-light level cameras to record the image, and then conventional cathode ray tube (CRT) monitors to display the resulting X-ray images. Unfortunately, such systems are bulky and poorly suited for portable applications. Further, the CRT displays do not always provide the contrast needed to readily see the X-ray image in bright ambient light conditions. Moreover, while some limited image enhancement techniques have been applied to such existing systems, the output image is still simply a real-time analog CRT image.